Wonder how it works.
Geoff ZS6GRL
Actually Geoff, you should link to the main site. Here
It is of more interest...
John ZS6WL
2013-11-29
2013-11-26
But Wait, There is more!
As promised last night, I am uploading the later pictures of the club's PC.
Cpu looking clean and shiny.
Having discovered that the heat sink fan assembly had a broken clip. I started to look around for a replacement. Of course the mounting holes on this "veteran" PC are different from the newer or latest fans. Luckily I had a broken motherboard lying in the garage. I proceeded to un-clip the identical assembly from the motherboard. I am glad I did, it taught me a lesson. The plastic pins that go through the pcb have small white plugs that need to be unplugged before you can remove the housing.
So I now had to disassemble and disconnect the motherboard from the chassis. Before forgetting where all the wires are plugged in, I took a picture.
My memory is not what it used to be. The phone's camera has proved invaluable for close up records of all sorts of things. Now I unplugged all the wires and unscrewed the mounting screws...
On the bottom of the motherboard:
It also confirmed the date of the PC's making. As I later discovered that the version of Windows XP was in fact the original. It was never updated because the installer had turned off the automatic updates. Windows XP was not even service pack 1 !
I then started to clean the cpu and the heatsink.
Hey wait a minute! What is that on the heat sink? After I had removed the large amount of thermal paste, I found the other thermal pad...
Which of course had never been used. So I unpeeled the pad to find this extra thermal transfer pad had never been used... No wonder the cpu got hot. It was working under a 'blanket'.
So I cleaned that off the aluminium heat sink as well. Re-applied some new thermal paste to both cpu and heatsink. Putting to good use an old credit card to smooth the paste onto the cpu and the heatsink and into a thin layer. The paste is only there to smooth out the rough surfaces of the cpu and heatsink. Also to present as little as possible 'thermal resistance'. So the heat generated in the cpu can be radiated away as efficiently as possible.
I put the PC back together and plugged in all the wires. Checked carefully that the plugs were all in/on the right pins/sockets. Then switched on. First I got into the BIOS setup. Only to discover - yes the battery was 0.5 Volt - flat. It should be 3 Volts. Replaced the battery. Switched on again. now the cpu temperature reached 42C and settled at that after about 5 minutes.
Then I booted the PC to Windows XP Professional. Only to find out that it was the first ever version of XP. Service Pack 3 will not install on anything less that service pack 1. The following six hours are a blur now... Now you know why I call it "Windwoes". At about 19:30 I switched it off and put it into the boot to take to the club.
Maybe some more later.
73 John ZS6WL
2013-11-25
AAAAAAAAAARGH! NOT AGAIN!
When I was at the club on Saturday, I took charge of the club's PC. This was pre-arranged and as the operators now bring their own laptops, I could remove it from the club.
Geoff ZS6GRL, had told me already that there were 'issues' with the PC. It would hang and he 'cured' the 'issue' by removing the display card and replacing it...
Well, when I got it to the workbench, I switched it on and it told me to 'Check System Health!'. So I did...
69C is far too high for the cpu after just switching on.
It is an 'old' PC and the assumption is that the thermal paste has gone bad...
But when I opened it up and checked the heat sink assembly and fan, I found this :-
I could not believe my eyes. There is the remains of a label stuck to the cpu! It has about a third of the thermal transfer area insulated from the heat sink.
I also had discovered that the plastic retaining clip had broken on the fan assembly. The remains can be seen at the top area. Obviously this has to be cleaned and the plastic retainer replaced.
Some of you reading this will already know about 'Murphy's Law'. This is one instance where he would jump in. This is an 'old' PC with an old fan assembly...
Of course the new [modern] fans will not fit the holes on the motherboard...
Part 2 to follow, after I have fixed the PC.
John ZS6WL
Geoff ZS6GRL, had told me already that there were 'issues' with the PC. It would hang and he 'cured' the 'issue' by removing the display card and replacing it...
Well, when I got it to the workbench, I switched it on and it told me to 'Check System Health!'. So I did...
It is an 'old' PC and the assumption is that the thermal paste has gone bad...
But when I opened it up and checked the heat sink assembly and fan, I found this :-
Some of you reading this will already know about 'Murphy's Law'. This is one instance where he would jump in. This is an 'old' PC with an old fan assembly...
Of course the new [modern] fans will not fit the holes on the motherboard...
Part 2 to follow, after I have fixed the PC.
John ZS6WL
2013-11-15
Ubuntu Amateur Radio Software - fldigi and others
I have just caught another link from a Radio Amateur who is using the Raspberry Pi to test his H.F. filters...
But that is not what I wanted to blog about. It is this:-
I was looking for an 'equivalent' to HRD but for Linux Ubuntu. This PC and OS (operating system) has proven to be the most useful for my hobby, Amateur Radio. So whilst I had already compiled the beacon program for Ubuntu. I wanted to see if there was anything else.
fldigi is available for Windwoes as well. So those of you with XP etc, can now make use of the 'open source' software as well.
Maybe you should read this first:-
This all came about because the latest Elektor Post arrived in my inbox and this caught my eye:-
Wow! He only did it to please the RSGB...
Some reading for the weekend and those not going on the field day.
73
John ZS6WL
2013-11-14
Contesting
History of contesting
The
origin of contesting can be traced to the Trans-Atlantic Tests of the early
1920s, when amateur radio operators first attempted to establish long distance
radiocommunications across the Atlantic Ocean on the short wave amateur radio
frequencies. Even after the first two-way communications between North America
and Europe were established in 1923, these tests continued to be annual events
at which more and more stations were successful in establishing two-way
contacts over greater and greater distances. In 1927, the American Radio Relay
League, which had been principal in organizing and publicizing these tests,
proposed a new format for the annual event, encouraging stations to make as
many two-way contacts with stations in other countries as possible. The 1928
International Relay Party, as the event was renamed, was the first organized
amateur radio contest. The International Relay Party was an immediate success,
and was sponsored annually by the ARRL from 1927 through 1935. In 1936, the
contest name changed to the ARRL International DX Contest, the name under which
it is known today.
Contesting
One of
the best ways of getting the most out of your investment in amateur radio is to
take part in contests. In South Africa we have numerous contests that mostly
take place over weekends which gives you the opportunity to compete against
your local peers. There are also plenty of overseas contests where you have an
opportunity to test your skills against your international peers. Your level of
intensity in these contests depends on whether you just want to take part for
fun or aim on winning the contests.
To
explain more about the terminology you will encounter in contests, I have taken
the following FAQ (Frequently Asked Questions) from an article written by
Andrew Roos ZS5AA with his permission
Everyone
has their own reasons. Some of mine are: to sharpen my operating skills, to
learn to get the most I can out of my equipment, to compete against my peers,
to be a part of the community of contesters.
The
winner in each category is the station which gets the most points in that
category.
Each QSO
will score a certain number of points. The number of points scored for a QSO
may depend on the location of the station contacted - for example in the CQ
Worldwide DX contest stations on the same continent as yourself count 1 point
each, stations on a different continent count 3 points and contacts between two
stations both located in North America count 2 points. In other contests, QSOs
for certain stations may count for more points than QSOs with others - for
example, in the ARRL 10m contest, contacts with stations holding Novice or
Technician Plus class licenses count more than contacts with other license
classes. In contests which allow you to work in different modes (for example,
CW and SSB) the number of points may also depend on the mode.
As well
as getting points for each QSO, most contests allow you to get multipliers
from certain QSOs. For example, you might get a multiplier for every different
country ( DXCC entity)
you work on each band during the contest. Your final score for the contact will
then be calculated by multiplying the total of all your QSO points by the
number of multipliers you worked. For example, if you worked 100 stations at 2
points per QSO and 20 multipliers, then your total QSO points would be 100 x 2
= 200, and your multiplier is 20, so your final score would be 200 x 20 = 4000
points.
Entities
correspond roughly to countries and administrative territories, but they also
may be islands and even reefs if they meet criteria set by the ARRL, which
administers the DX Century Club (DXCC) award and decides what qualifies as an
"entity".
Scarborough Reef
The world
is divided into 40 "CQ Zones" which are used as multipliers for some
contests. Get further information and a map showing the different zones at www.cq-amateur-radio.com/wazmain.html.
That
depends on the particular contest. Some contests are limited so a single band -
for example, the ARRL 10m contest is (not surprisingly) for 10m only. Many
contests allow operation on all the pre-WARC HF bands - that is: 160m, 80m,
40m, 20m, 15m and 10m. Other contests are for VHF bands only. However note that
contesting is never permitted on the WARC bands: 30m, 17m and 12m. This is so
that amateurs who do not enjoy contesting can take refuge on the WARC bands
during contests.
The WARC
bands are the 30m, 17m and 12m bands. They were named after the World Amateur
Radio Conference in 1979 at which these bands were allocated for amateur use.
The WARC bands may not be used for contesting.
Different
contesters have different preferences and budgets. Some like to work on their
own, others prefer to be part of a team. Some can afford high-power stations,
others prefer to compete with a "barefoot" or QRP transceiver. By
dividing a single contest into a number of different entry categories, all
contesters can share the fun and contribute to the contest, while competing
against similarly equipped stations in the same category.
That
depends on the contest, but the entrance categories for the CQ Worldwide DX
contest are a good example of a fairly extensive list of possibilities:
- Single Operator High - a
single operator, maximum power 1.5 KW, no DX alerting assistance (for
example, DX cluster spots) allowed.
- Single Operator Low - a
single operator, maximum power 100W, no DX alerting assistance allowed.
- Single Operator QRPp - a
single operator, maximum power 5W, no DX alerting assistance allowed.
- Single Operator with DX
Spotting Net (also called "Single Operator Assisted") - a single
operator, maximum power 1.5 KW, passive use of spotting nets allowed.
- Multi-Operator, Single
Transmitter (also called "multi single" or "MS" for
short) - any number of operators, but only one transmitted signal allowed
at any time. The additional operators will often be listening for new
multipliers, and passing the information on to the one transmitter
operator.
- Multi-Operator, Two
Transmitter (also called "multi two") - Any number of operators,
but only two transmitters. In CQWW, both transmitters may work any
stations. In some other contests there are strict restrictions on what the
second transmitter may do - for example, it may only be allowed to work
new multipliers.
- Multi-Operator, Multi
Transmitter (also called "multi multi") - Any number of
operators, operating any number of stations, but with only one transmitted
signal on each band at any time. In many cases a "multi-multi"
station will have a dedicated transmitter for each of the contest bands.
Note that
in CQWW, single operator entries can choose to be all-band, or only to work a
single nominated band.
These are
all abbreviations for contest entry categories:
- SOLP - Single Operator Low
Power
- SOHP - Single Operator High
Power
- SOAB - Single Operator all
band
- SOSB - Single Operator
Single Band, often includes the band, e.g. "SOSB/80" for a
single band entry on 80m
- M/S - Multi/Single - Many
operators but only a single transmitter
- M/2 - Multi/Two - Many
operators with two transmitters
- M/M - Multi/Multi - Many
operators with many transmitters
It is a
worldwide computer system on which DX stations are reported
("spotted"). It can be accessed via Packet Radio or on the Internet
at www.dxsummit.com. You are only allowed to make
use of DX Cluster spots if you are entered in an "assisted" class. No
matter what class you are entered in you may not enter your own station into
the DX cluster, this is called "self spotting" and is illegal in all
contests.
To make a
serious attempt at an international contest, yes. Most of the smaller stations
that enter a contest spend much of their time answering other stations that are
calling CQ. This is known as "search and
pounce" -
you search for a station you need, and then pounce on it by replying to its
call. However since you can only work a station once on each band and mode,
before you reply to the CQ, you need to know whether you have worked the
station before, and unless you have a photographic memory a computer logging
program is by far the best way to do this. Contesters are a very friendly bunch,
but calling the same station five or six times on the same band during a major
international contest will test the patience of even the most saintly
participant. Of course if you are fortunate enough to be even moderately rare
DX (ZS for example), then you can get by with calling CQ yourself and waiting
for a reply, log this on paper and later remove the duplicates
("de-dup" the log) by hand. This is what I did in my first major
contest, but after manually de-duping 475 QSOs, which took me a whole day, I
went out and bought a logging program.
Note that
for many of the smaller state or national contests, you can get by without a
logging program as there are few enough entrants that you can remember who you
have worked or look it up on your paper logs. These contests can be great fun
and are excellent practise for the "big ones".
There are
many different, some commercial ones, which you have to pay for, and some which
are free. Popular commercial programs include WriteLog
for Windows, TRLog and SD. Writelog has a Windows
graphical user interface. Although originally written for DOS, TRLog will also
run under most versions of Windows. SD is available in two versions, one which
runs character-mode under Windows, and one for DOS. Free contest logging
software includes CT, also originally designed for DOS, and the
open-source N1MM logger for Windows. N1MM has been adopted by the SARL as the
logging software that is recommended. N1MM is the only logging program that
has all the templates for our contests
included which makes it a pleasure to use.
First, be
aware that logging programs come in two different flavours - general logging
programs designed to maintain a normal station log, and specialized contest
logging programs. The difference is that contest logging programs have contest
scoring rules "built in" for major contests, so they will
automatically keep track of your score, tell you whether you can work a
particular station for the contest, and other contest-specific time saving
features. Needless to say, you want a program designed for contest logging.
Then make sure it supports the contests you want to enter, since having the
contest programmed into the software for you is a real time saver. If you don't
know exactly which contests you want to enter, then at least see how many
contests it supports. Also consider the ease of adding new contests yourself if
you have to. Some programs, like WriteLog for Windows, require programming
skills to do this while with others, like TRLog, you can add new contests by
editing a configuration file. Also look for a program that can interface with
the rig(s) you use or are likely to use. Having the logging program
automatically pick up the band and mode your rig is set to is a great time
saver and eliminates a common source of costly errors. Many logging programs
can also turn your beam automatically for you to point at the station you are
working, so if you want to use this feature then make sure the program is
compatible with the rotator(s) you are using. Finally, make absolutely sure
that the logging program can export the log file in the standard "Cabrillo" format, which is used to
submit logs for most contests. All decent logging programs can interface to
your rig's key jack to send CW automatically. This is a great feature as it
allows you to send exchanges while capturing information into the logging
program.
Cabrillo
is a standard format for submitting log files to contest organizers so they can
be checked and scored by computer. Although different logging programs store
the log files in different formats, most have the ability to export to Cabrillo
format for submission.
There are
a couple reasons to connect your computer to your rig. First, so it can send CW
automatically and/or PSK31 or RTTY depending on the contest. Some logging
programs also provide a "voice keyer" which allows you to record
messages and then replay them over the air. This is great for calling
"CQ" in a phone contest, for example. For this you need a computer
soundcard interface with support for CW keying. A simple example can be found on my web site. The
second reason is so the logging program can keep track of the band and mode of
your transceiver. This may require a proprietary interface from the transceiver
manufacturer. Many of these interfaces will also allow the computer to control
the transceiver, so for example you can change frequency simply by typing the
new frequency on your computer.
Just the
rig you use every day. That's not to say that some rigs aren't better for
contesting than others, but just about any rig will do to start. If you plan to
buy a new rig for contesting, then look for one with a "strong"
receiver which can receive weak signals in the presence of very strong signals
without overloading. The "blocking dynamic range",
"intermodulation dynamic range", "third order intercept"
and "phase noise" specifications found in most technical reviews are
important indicators of this.
Also,
note that it is a good idea to have your commonly used functions such as filter
selections, if width and shift (if available), notch filter, attenuator, RF
gain, mode, and band switch available on the front panel, to avoid having to
wade through a menu system in the heat of battle. This means that the compact
transceivers designed primarily for mobile operation may not be the best choice
in a contest. The ability to interface the rig to your computer so the logger
can automatically enter the correct band and mode is another useful feature
that is found on most modern rigs. A narrow (250 or 500 Hz) filter is almost
essential for CW contests.
Amongst
current production HF transceivers the Elecraft K2, Icom IC-756 Pro 2, Ten-Tec
Orion and Yaesu Mk V FT-1000 MP are some of the best. However note that these
are not beginner's radios (with the possible exception of the K2, but this must
be constructed from a kit and so is best suited to someone with prior
construction experience), so if you have no prior operating experience it may
be better (not to mention cheaper) to start off with an entry-level or
mid-range radio. There are also some excellent radios available at very
reasonable prices second-hand, such as the ICOM IC-765, Kenwood TS-850S, Ten
Tec Omni VI Plus and the Yaesu FT-990 as well as earlier versions of the
FT-1000 (both the FT-1000D and the original 'MP are excellent radios) and the
IC-756 Pro.
The
object is to make as many QSOs as possible in a limited time, so "QSO
rate" - the number of QSOs per hour - is (almost) everything. Hence all
"unnecessary" parts of the QSO are omitted, leaving only the required
essentials - call signs, 599 signal reports and a serial number or zone number
if required by the rules. Be sure to check the rules to see what the required
exchange is for each contest you enter.
Read the
contest rules and decide which category you will enter. Test your station and
antennas. Have a look at the expected propagation and draw up an operating
schedule showing when you expect to operate on which bands, and where your beam
will be pointing. (This schedule will change during the contest as conditions
unfold, but you should at least have an initial plan.) Stock up on fast food -
microwave meals are my favourite. Set up your computer, check that the logging
program is interfacing with the PC correctly, and ensure that you select the
right contest in the logging program. Try to get as much sleep before the
contest starts as possible so you can work long hours during the contest
itself. Feed your pets. Read the contest rules (again) and make sure you
understand the exchange format, multipliers, sequence numbers, entry
categories, power restrictions etc. Accurately set your computer clock so the
QSOs will be logged at the correct time.
In order
to be listed in the results, you will need to submit your log to the contest
organizers. Most of the major contests these days prefer electronic logs,
usually in Cabrillo format, as they can be automatically checked and scored.
Smaller (e.g. national) contests may prefer paper logs. In most cases if you
have not used computer logging then paper logs will be accepted. However many
contests will not accept paper logs printed by a computer logging program.
After all if you have the log on computer then they don't want to have to type
it in again. The address for submitting your logs can be found in the contest
rules.
"Massaging
your log" - for example, checking callsigns in a callsign database and
then correcting those found to be in error - is generally frowned upon by
contesters, although it may not be strictly illegal.
A
"busted call" is a call which you captured incorrectly during the
contest. You will generally lose points for busted calls or incorrectly logged
serial numbers.
If you
are responding to a CQ, then wait for the station to call CQ again so you can
copy the call correctly. If you are calling CQ, then send "CL?" and
the other station will repeat his or her callsign. If conditions are poor, then
you may have to ask a couple of times, but this is much better than getting the
callsign wrong - which will cost you penalty points for the contest - or not
entering the QSO in your log file, which is very unfair to the other station
and will cost him or her penalty points. Note that although some programs (e.g.
WriteLog) have the ability to mark a QSO as "unclaimed", the Cabrillo
format used to submit contest entries has no such mechanism, so QSOs marked as
"unclaimed" in the log file will just not be included in the Cabrillo
file. It is very bad karma to do this unless you are absolutely sure
that the other station knows they are not in your log, otherwise they might
submit the QSO and be penalised for it.
You hear
unusual callsigns during contests for two reasons. First, some administrations
reserve special short or unusual callsign sequences specifically for use during
contests. For example, in Britain callsigns with a single letter in the suffix
like "M5A" or "GM1A" are reserved for contest use. In France,
the prefix "TM" is allocated to contest stations rather than the more
usual "F" prefix, for example "TM6X". A short callsign
gives the station an advantage because it is faster to send and less likely to
be copied incorrectly. Unusual prefixes are attractive because in some contests
like the CQ Worldwide WPX (Worked all Prefixes) contest, each unique prefix
counts as a multiplier, so the more unusual prefixes will attract more calls.
That happens in other contests as well.
The first time I heard a "TM"
station I was convinced I had found some rare DX, and was somewhat disappointed
when I discovered it was located in mainland France. Some
countries have even issued callsigns without a digit following the national
identifier. For example, the callsign "D4B" is issued by Cape Verde
which has the national identifier "D4", so there is no digit
following the national identifier - the "4" is part of the national
identifier. However Article 19 of the ITU Radio Regulations was amended by the
World Radio Conference 2003 (WRC-03) making it mandatory to have a digit
following the national identifier, so it is likely that such callsigns will be
phased out.
Another
reason for unusual prefixes is that many stations operate temporarily from a
foreign country, usually to make themselves more sought after in the contest.
For example, American stations are two a penny in most contests, but an
American visiting the Bahamas is an attractive multiplier. Operators visiting a
foreign country may be allocated a "normal" callsign for the country
they are visiting, but will often use their home call either preceded or
followed by the country (and possibly region) prefix of the country they are
visiting. For example, KD4D operating from South Africa would use the callsign
ZS/KD4D, while the same station operating from Canada would use a callsign like
KD4D/VE3. Note that the Morse code for the "/" symbol is
"dah-di-di-dah-dit", and it is pronounced "stroke" on
phone.
Unfortunately
there is no standard as to whether the national identifier of the country being
visited should precede or follow the home call. The CEPT agreement, which is
the largest reciprocal licensing arrangement covering Europe, North America and
some other countries, specifies that the national prefix should precede the
home call. However other reciprocal agreements, like the one between the United
States and Canada, specify that the national identifier should follow the home
call and even within the CEPT agreement there is one exception (Peru).
Also note
that following WRC-03 it is now legal for amateur callsigns to have a suffix of
up to four characters (even more for special event stations), and the suffix
may use both letters and digits provided that the last character is a digit. So
in future contests you may hear callsigns like "ZS1234A" or even
"22222A"! The latter would be from Britain, which has been allocated
the national prefix "2".
So the
best advice on callsigns is to expect the unexpected, and log each callsign exactly
as received.
If you
are using Logbook of the World then by all means. If you are
using QSL cards then this is likely to take a lot of time and money due to the
number of contacts made in a contest. My policy is that in contests I only QSL
on request, which normally means the other station sending me a direct QSL with
a self-addressed envelope. This differs from my normal non-contest policy which
is to QSL every contact via the bureau unless otherwise agreed. But whatever
you decide, please don't enquire about QSLs on air during the contest. If you
work a station you need, then QSL direct with a dollar bill or IRC after the
contest.
73 Geoff Levey ZS6GRL
73 Geoff Levey ZS6GRL
2013-11-13
Long wire antenna lengths
Long wire antenna lengths to use and to avoid
http://www.hamuniverse.com/randomwireantennalengths.html
73 Geoff ZS6GRL
http://www.hamuniverse.com/randomwireantennalengths.html
73 Geoff ZS6GRL
Another take on Hex Beams
Another take on Hex Beam antennas
http://midcoast.com/~w1gql/hex/buildyour.htm#construct_section
Geoff ZS6GRL
http://midcoast.com/~w1gql/hex/buildyour.htm#construct_section
Geoff ZS6GRL
2013-11-09
Thanks Willem!
Thanks Willem!
At last some 'input' from a committee member. He sent me this link:-
Symmetrical Matchboxes
Which has another link to the 'S-Match' here:-
S-Match
At last some 'input' from a committee member. He sent me this link:-
Symmetrical Matchboxes
Which has another link to the 'S-Match' here:-
S-Match
These links have a very interesting proposition for balun fed 'symetrical' matching circuits for aerial feeds. They also have core information for use with moderate power levels. (100Watts)
Enjoy!
John ZS6WL
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